The Definitive Guide

[Custodio Groves]

NoteThis book has been published by Chapman & Hall/CRC. The online version of this book is free to read here (thanks to Chapman & Hall/CRC), and licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

However, the original version of Markdown invented by John Gruber was often found overly simple and not suitable to write highly technical documents. For example, there was no syntax for tables, footnotes, math expressions, or citations. Fortunately, John MacFarlane created a wonderful package named Pandoc ( ) to convert Markdown documents (and many other types of documents) to a large variety of output formats. More importantly, the Markdown syntax was significantly enriched. Now we can write more types of elements with Markdown while still enjoying its simplicity.

In a nutshell, R Markdown stands on the shoulders of knitr and Pandoc. The former executes the computer code embedded in Markdown, and converts R Markdown to Markdown. The latter renders Markdown to the output format you want (such as PDF, HTML, Word, and so on).

The rmarkdown package (Allaire, Xie, Dervieux, McPherson, et al. 2023) was first created in early 2014. During the past four years, it has steadily evolved into a relatively complete ecosystem for authoring documents, so it is a good time for us to provide a definitive guide to this ecosystem now. At this point, there are a large number of tasks that you could do with R Markdown:

Please do not underestimate the customizability of R Markdown because of the simplicity of its syntax. In particular, Pandoc templates can be surprisingly powerful, as long as you understand the underlying technologies such as LaTeX and CSS, and are willing to invest time in the appearance of your output documents (reports, books, presentations, and/or websites). As one example, you may check out the PDF report of the 2017 Employer Health Benefits Survey. It looks fairly sophisticated, but was actually produced via bookdown (Xie 2016), which is an R Markdown extension. A custom LaTeX template and a lot of LaTeX tricks were used to generate this report. Not surprisingly, this very book that you are reading right now was also written in R Markdown, and its full source is publicly available in the GitHub repository -book.

R Markdown documents are often portable in the sense that they can be compiled to multiple types of output formats. Again, this is mainly due to the simplified syntax of the authoring language, Markdown. The simpler the elements in your document are, the more likely that the document can be converted to different formats. Similarly, if you heavily tailor R Markdown to a specific output format (e.g., LaTeX), you are likely to lose the portability, because not all features in one format work in another format.

Last but not least, your computing results will be more likely to be reproducible if you use R Markdown (or other knitr-based source documents), compared to the manual cut-and-paste approach. This is because the results are dynamically generated from computer source code. If anything goes wrong or needs to be updated, you can simply fix or update the source code, compile the document again, and the results will be automatically updated. You can enjoy reproducibility and convenience at the same time.

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This article summarises all my knowledge and experience, and it took me 6 months to get together. I believe, anyone, newbie or pro, could find some new useful info inside of it. There are already hundreds of articles, dozens of guides. And some of them are really good. However, there was still a need for the comprehensive photography composition guide nicely presented and easy to follow. I did my best to keep it simple, concise and easy to understand with lots of goodies to download for future reference. Also, I keep it as short as possible with zero fluff for such a massive amount of material. Less talk, more practical info with examples, charts and graphs.

Side note: Most of the time I shoot landscapes and, therefore, most of my examples are some nature scenes. While street photography or portrait photography have their own specifics, they still follow the same composition principles. I believe this guide can be easily extrapolated for whatever other genres you shoot.

As you can see, as a general rule, a photographer has much less time than an artist to decide on the final look of the photograph. That is the reason to take an extra shot or two just in case you missed some aspect with the first one.

Before going deep into the techniques, we need to understand what the photography composition actually is, how it is created, what key points it has, how it affects our perception and what its capable of.

The most challenging frame to shoot is square. By its nature, it is very stable and has zero dynamics. So, you should have a perfect reason to select a square format for your shot. The subject should be very stable by itself of lack any dynamics. The good example would be some patterns or something symmetrical.

The rule of thumb is to choose a horizontal frame when the majority of the compositional lines are horizontal and vice versa. Sometimes you could do the opposite to increase tension, i.e., include a vertical subject, In this case, make sure to leave a lot of breathing space around it.

Just like with positioning high contrast objects near the frame edges, the corners are even more critical. Always check the corners before pressing a button and avoid anything distracting. Any object near the corner immediately drags an enormous amount of attention, and the eye keeps jumping back to it. The key to the composition is simplicity and clarity.

The bigger the object you include in the scene, the harder it is to balance it with something. Sometimes a massive rock on the foreground chokes the whole photo. So, the balance also applies to the object-to-scene relation.

Please note, this is important for understanding, balance is not opposite to dynamism. Balance is contrary to off-balance. The decision to make a balanced or unbalanced shot is entirely up to the creator as they have a different influence on the viewer.

If we have just one layer, it may look flat and dull. If we have two, they could compete with each other. Three will allow the viewer to look smoothly deeper and deeper into the shot. However, take a telephoto lens and zoom heavily in the green hills with some trees and make a shot. There is just one distant plane with everything in it. This one is a special case, where it works. Another excellent example of the reduced number of layers is when the landscape is very graphical, like the foggy morning. In the photo where competition is part of the story, feel free to include two layers to emphasise it.

For the curious: Rule of Thirds originates from the Rabatment of Rectangle. This technique builds two squares for any aspect ratio rectangle. Believe it or not, for the regular 3:2 aspect ratio, this rabatment is precisely on the thirds.

This shape is very dynamic and pleasing. It curves through the shot giving the ability to browse all parts and leading to the main subject. Unlike a diagonal, which is very direct and straightforward, the curve is more gentle and catchy. Such compositions look most natural, and the viewer has zero chance to escape the flow.

The rule of odds suggests that we find an uneven number of objects in the photo more appealing than an even number. The reason for that is again stability vs dynamism. The even number of objects suggests balance and lack of movement and of course, the bigger the number, the harder to spread attention between all subjects. Also, two elements imply competition, opposition, and tension, or just a dialogue. Three elements convey a story and produce a dynamic balance. There is always something in the middle surrounded by other items thus giving a visual anchor.

I know, this last image will raise a lot of questions. The main idea here is that if you can visually group elements, they become a single element. It depends on the actual picture and visual weight of the items in it.

The wrong area type can ruin the shot. For instance, you have a dynamic and lively seascape with a rushing wave. The closed area in this case could choke it, stop and cut the action. Sometimes, this effect is not strong enough to actually ruin anything but it affects the mood, and you should consider it.

You need to find something that could form a frame around your main subject. You can use cliffs, tree branches, keyhole, broken fence, anything. It adds another dimension to the photo and adds context. Frame within frame gives an extreme accent to the centre. Also, more often than not, this type of composition works excellent with symmetrical shapes and central composition.

Simply saying, the rhythm is a recurring pattern of elements differentiating by strong or weak elements or varying conditions. This definition means, to form a rhythm, you need something repeating over time, and the repetition itself should create a pattern. You can build multiple rhythms in a single shot, and that makes a photo even more interesting.

For example, a simple repetition of lines is a very sketchy rhythm. A repetition with decreasing length is already more appealing than a bunch of similar objects. Another modification to the initial example of repeating lines is to add a few longer gaps (also repeated over some intervals). Think of it as music. Would your pattern form a nice sounding beat?

You can build a rhythm around the lines, objects, groups of objects, colours, tones, flares, light and dark areas, etc. Anything goes. Rhythm is a repetition that encourages the eye to move in a particular direction.

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